afuller

Noticed lately my cavalier "surges" when driving but NOT while in idle noticed it does it with or without AC and or heat on. At first I thought it might be the fuel filter so I did the following I changed inline fuel filter, air filter, all spark plugs, change the oil, change air temperature sensor, and put Lucas injector cleaning fluid in gas. After all of this problem continued, it does not impaired driving or speed or acceleration but does concern me wondering if you guys could give any suggestions whether it be the fuel pump or anything else I should know about again the problem continues while driving but NOT while idle.

Headache Ball

Clean your throttle body. Sounds as if your IAC is playing games. A lot of times that can be fixed by removing the throttle body and scrubbing the daylights out of it. My 03 does something similar with an idle flare or a decel stall. I found a TSB for getting the PCM reflashed, so now I just need to get it done.

afuller

awesome thanks for the throttle body suggestion I will try that but I didn't quite understand the second half of your message, what is the TSB and PCM and are they something that I should look into if my car it is a normal fuel vehicle, Cavalier LS 5 speed manual 110,000 miles on it thanks for the help hope to hear from you soon

PS I was thinking its about time to change my timing belt have you done so or is it something better to have done at a shop? Timing is usually a sensitive project

BW56

My 02 surges as i slowly excelerate in first gear (automatic). Its not really noticable any other time. Its multi port injected. Two years ago i replaced the head. Where should i look now? Bob

Headache Ball

Your Cavalier doesn't have a timing belt= no problem there! They have a chain.
General Motors Technical Service Bulletin (TSB) 04-06-04-063 calls for reprogramming the Power Control Module (PCM)
For the record, I have an 03 LS 5 speed with 233,000 miles on it so far.

Bob, I will see what I can find on yours, but I am leaning toward a similar issue.

afuller

Haha thanks, I never looked to see if it was a chain our belt, that being said is there any maintenance our replacing to the chain? Also, How would I go about reprogramming the PCM? What does reprogramming the PCM do for the car? Also thanks for the help Headache Ball, I await your next reply.

afuller

I would like to edit one of my previous post and say it happens more often during acceleration less during constant speed aka cruise control and never during idle or deceleration with that being said I'm not sure if the TSB 04-06-04-063 is the fix because upon reading on that it fixes a deceleration stalling issue with the 02-04. if you have any enlightenment on the subject please let me know I am anxious to get this issue resolved.

Headache Ball

Cool. Mine does exactly what is described in the TSB. Matter of fact it does BOTH. I'll push in the clutch when I approach the security gate at work in the morning and that sucker will idle up at 1800 rpm. Leave outta here in the afternoon, the first (only) stoplight is about a mile out of the gate, push in the clutch and that thing idles down to 450 rpm and sometimes just stalls. Drives me nuts. The PCM has to be reprogrammed by the dealer unless you know someone with a tech2. As far as maintaining the chain, just keep that oil changed. I wouldn't replace it until I had to, and mine has been fine for 10 years now. I hope to have some time today to chew on your issue some more, but is really sounding like that throttle body and IAC valve need to be cleaned. I am leaning the same way on Bob's 02 as well.

If you remove the IAC valve to clean it---> Once you reinstall it, before starting the engine, turn to key on and let it sit there for 10-30 seconds, then turn the key off. Then go ahead and start it. It lets the coputer reset the valve position in case the pintle moved during removal, cleaning, or installation.

afuller

is that IAC part of, inside, or underneath the throttle body? Where can this be located? Thanks again for allthe help, I'm learning a lot.

Headache Ball

The red star indicates the IAC valve. It is held in by a Torx screw, I believe a T15 or T20

The blue spot indicates the TPS, Throttle Position Sensor.

That big hunk of aluminum they are attached to is your throttle body, you can see on the right hand side where the throttle cable attaches.
Hope that helps.